Priming arrangement for centrifugal pumps



Dec. 1, 1953 F. A. WATEROUS 2,660,956

PRIMING ARRANGEMENT FOR CENTRIFUGAL PUMPS Filed June 3, 1949 3 Sheets-Sheet 1 Had A. l iazerous Dec. 1, 1953 F. A. WATEROUS 2,660,956

PRIMING ARRANGEMENT FOR CENTRIFUGAL PUMPS Filed June .5, 1949 3 Sheets-Sheet 2 ffea. )Vaterous Dec. 1, 1953 F. A. WATEROUS 2,660, 56

PRIMING ARRANGEMENT FOR CENTRIFUGAL PUMPS Filed June a. 1949 s Sheets-Sheet s 1111. '11 I 1; IIIIIIIA 'lllllll Patented Dec. 1, 1953 PRIMING ARRANGEMENT FOB CEN- TRIFUGAL PUMPS Fred A. Waterous, St. Paul, Minn, assignor to Waterous Company, St. Paul, Minn., a corporation of Minnesota Application June 3, 1949, Serial No. 96,990

8 Claims. (Cl. 103-107) My invention relates to an improvement in priming valve for a centrifugal pump wherein it is desired to provide a simple and effective device for automatically shutting off the priming connections between the volute and the discharge manifold after the pump has been successfully primed.

For a number of years it has been common practice to provide a valve chamber on a centrifugal pump and to connect this valve chamber with a plurality of high points on the pump from which air is to be withdrawn during a priming operation. For example many pumps have been produced which provide a valve chamber which is connected. to all of the pump volutes as well as to the discharge manifold. By manually moving this valve into position to form a connection between the priming pump and these by-passes, the air may be removed from the upper extremities of the volutes as well as from the discharge I manifold so that the water will enter these parts and a water seal will be produced. Such an arrangernent has been found highly advantageous over the more common method of connecting the priming pump to the intake manifold as air trapped within the pump volutes has a tendency to break the suction after the pump is started.

t is an object of the present invention to provide a valve which is normally closed and which operates automatically to close the passage to the volutes as soon as pressure is produced in the discharge manifold. At this point in the operation of the pump, the pump has usually been successfully primed and should continue in operation as long as the liquid supply is continuous.

A feature of the present invention lies in the provision of a simple flat spring valve which is arranged between a pair of castings forming parts of the pump. This spring valve is provided with a pair of spring fingers which extend over the ports leading to the upper ends of the volutes or impeller chambers. These spring valves may readily spring away from the ports when the pressure within the volute chambers exceeds that of the valve chamber and may flex into position to close the ports when the pressure within the valve chamber exceeds the pressure within the impeller chambers.

A feature of the present invention lies in the provision of a simple sheet of resilient material which is formed to provide an encircling frame and a pair of inwardly directed spring fingers in tegral therewith. The valve may be produced at an extremely low cost by a single punch press operation and needs no special machining or mounting as it fits between the pump housing and the valve chamber casting.

An added feature of the present invention lies in the provision of an automatic valve arranged to close a plurality of by-passes and which normally tends to hold the Icy-passes closed. When the air is being evacuated from the valve chamber by the priming pump the pressure within the valve chamber is less than the pressure in the bypass ports over which the valve extends so that the valves spring into open position to permit evacuation of air through these by-passes. The valve chamber is also connected by a by-pass to the discharge manifold. When the pressure within the discharge manifold exceeds the pressure within the individual impeller chambers, the spring will be urged closed by discharge pressure within the valve chamber. When the pressure in the discharge manifold equals that in the impeller chambers, the valve will close the ports because of the resiliency of its body.

These and other objects and novel features of my invention will be more clearly and fully set forth in the following specification and claims.

In the drawings forming a part of m specification:

Figure 1 is a top plan view of a centrifugal pump showing the arrangement of the parts therein.

Figure 2 is a side elevation view of the pump disclosed in Figure 1.

Figure 3 is a perspective view of the valve removed from the pump.

Figure 4 is a top plan view of a portion of the pump showing the location of the valve.

Figure 5 is a horizontal section through the valve and valve chamber.

Figure 6 is a sectional view through the valve chamber, the position of the section being incheated by the line 56 of Figure 5.

Figure 7 is a sectional View on a vertical plane through the pump showing certain of the bypass arrangements, the position of the section being indicated by the line 'll of Figure 4.

Figure 8 is a sectional view through the pump on a plane parallel to the section of Figure 7, the position of the section being indicated by the line 8-3 of Figure 4.

Figure 9 is a diagrammatic view showing the general type of pump on which the valve is used.

The pump A illustrated in the drawings includes a pair of parallel impellers i E3 and I I which are shown mounted upon a common drive shaft (2. The impellers are supported within impeller chambers 13 and M which are provided with connected volutes l and i6 respectively.

In the form of construction illustrated the volutes are angularly spaced so that they branch away from the impeller chamber at different relative locations. As indicated in the diagrammatic view, Figure 9, one volute is directly connected at ll to the discharge manifold I9. In actual practice the volute i5 inclines upwardly and branches laterally slightly into the discharge manifold. The volute i5 is connected to a bypass 28) leading through a transfer valve 2|. When the transfer valve 2! is in the position illustrated in full lines in Figure 9, the discharge from the volute it extends into the axial intake chamber 22 of the impeller H. A flap valve 23 is provided in the intake passage 24 to the impeller I leading to the intake manifold 25. The flap valve 23 is closed when the transfer valve 2i is in the position shown in full lines as the pressure within the intake passage 24 exceeds the pressure within the intake manifold 25.

When the transfer valve 2! is in the position shown in dotted out in Figure 9 of the drawings, the lay-pass 26 leads to a by-pass conduit 26 connected to the discharge manifold H}. Thus the two impellers may be arranged either in series or in parallel.

In actual construction the pump A is provided with a discharge manifold passage portion 2'5 which is between the volutes l5 and Hi. The discharge manifold is provided with a transversely extending rib or enlargement 29. At its outer extremity this rib or enlargement 29 is secured to a valve casing 3!] having a central tubular connection 3! leading thereto. The valve casing 39 is provided with a relatively shallow valve chamber 32 communicating with the surface of the chamber connected in abut ting relation to the enlargement 23.

As indicated in Figures i, 5, and l of the draw ings a laterally extending passage 33 is provided through the transverse rib or enlargement 29 to terminate above the volute l5. A vertically extending connecting passage 34 connects the lateral passage 33 to the volute so that a continuous by-pass is provided from the valve chamber- 32 to the volute 15 at a point near or at the upper extremity thereof. As also shown in Figure '7 of the drawings a horizontal pasr sage 35 extends through the boss-like end 36 of the rib or enlargement 28 and communicates with the valve chamber 32.

As shown in Figures 4, 5, and 8 of the drawings a transverse passage 37 extends through the enlarged end 35 of the rib 29 and terminates above the volute 55 or upper extremity of the impeller chem se it. A vertical passage 33 connects the upper end of the impeller chamber M with the transverse passage 31, thus formthe by-pass from the top of the impeller chamber to the valve chamber 32.

With reference now to Figure 6 of thedrawings, it will be noted that in the specific form of construction illustrated the transverse bypass passages 33 and 3'! are on substantially the same horizontal plane, while the by-pass passage 35 leading to the discharge manifold I9 is below the level of the other passages. The outer ends of these passages provide ports which may be flush with the outer surface of the en-- larged end 35 of the rib 29. The valve plate 49 is arranged to close the two passages 33 and 37, while the third passage 35 remains constantly opened.

.plate Mi.

The valve plate 40 is constructed as best i1- lustrated in Figure 3 of the drawings. This plate comprises a fiat sheet of resilient material such as spring bronze or the like. In the shape of construction illustrated the valve plate in cludes a generally rectangular frame 4| having laterally projecting side wings 42 and 43 which are provided with apertures 44 and 45 respectively. A generally rectangular aperture 46 is provided through the frame 4|, the shape of the aperture 46 depending upon the shape of the valve chamber housing 30. A pair of upwardly inclined fingers 4'! and 59 integral with the sides of the frame 4| extend into closely spaced proximity near the center of the frame and in position to overlie the ports or ends of the passages 33 and 31 as indicated in Figure 6 of the drawings. The valve housing and valve are held in place by cap screws 58 or other suitable means which extend through the valve casing and through the apertures 44 and d5 of the valve The tubular connection 3! on the valve casing 30 communicates with a check valve 5! which acts to close communication with the priming connection 52 when the pressure within the valve chamber 3! increases to a sufficient extent. The connection 52 is connected by a tubular connector 53 to a suitable priming pump 54 which is driven by the power supply source of the pump, or which may be driven by independent means if desired. The priming pump 54 may operate as long as is required to withdraw most of the air from the pump and intake thereto. Once the pump has been primed the impellers therein may be started into operation and the priming pump 54 may be disconnected. Any water drawn into the priming pump during the priming operation may be forced through a suitable outlet pipe 55 and discharged therefrom.

In the operation of the pump when it is desired to start the pump in operating the priming pump 54 is started. into operation. This priming pump acts to withdraw air from within the body of the pump, the air being withdrawn through the by-passes 33, 35, and El, and thus taking air from the upper extremity of both impeller chambers as well as from the discharge manifold. The withdrawal of the air from the pump acts to draw liquid into the pump until the impeller chambers are substantially filled. When the liquid level within the pump raises to such an extent that liquid is drawn through the by-passes, the impellers may be started in operation and the priming pump may be stopped.

Operation of the impellers causes a greater pressure in the discharge manifold 19 than in the impeller chambers, or at least causes an equalization of pressure therebetween. Higher pressure. in the discharge manifold causes the pressure to be increased in the valve chamber 32, thus pressing the valve fingers ll and 58 tightly against the ports at the ends of the by 'passes 33 and 31. If the pressure within the valve chamber 32 equals that within the impeller chambers 13 and 44, the resilience of the material forming the valve plate it acts to close the valve.

The provision of an automatic valve of the type disclosed is of advantage in the location where it is placed, as the priming force of the priming pump may be quickly applied to the impellers if the pump loses its prime. With such an arrangement the priming pump may if de sired remain connected until after the pump is in operation, thereby avoiding the danger of starting the pump prematurely and losing its prime as the impellers are started.

In accordance with the patent statutes, I have described. the principles of construction and operation of my priming valve for centrifugal pumps, and while I have endeavored to set forth the best embodiment thereof, I desire to have it understood that obvious changes may be made within the scope of the following claims without departin from the spirit of my invention.

I claim:

1. A centrifugal pump includinga housing having an impeller chamber therein, an impeller in said chamber, a discharge manifold connected to said impeller chamber to receive fluid therefrom, a pair of by-passes connected to said impeller chamber and to said discharge manifold, a valve housing secured to said pump housing to enclose the ends of said by-passes, a source of partial vacuum connected to said valve housing to partially evacuate the same, and a flat spring valve secured between said pump housing and said valve housing and including a spring arm normally overlying (the by-pass leading to the impeller chamber.

2. The structure described in claim 1 in which the fiat spring valve includes an outer frame having an aperture therethrough in registry with the end of the by-pass leading to the discharge manifold.

3. A centrifugal pump including a valve housing having an impeller chamber therein, an impeller within said chamber, a discharge manifold communicating with said impeller chamber, a boss on said pump housing having a substantially flat outer surface, a pair of by-passes in said pump housing extending through said boss, one of said by-passes communicating with the discharge manifold and the other of said by-passes communicating with the impeller chamber, a valve housing removably secured to said boss, a valve plate secured between said valve housing and said boss to overlie a portion of the boss, said valve plate including a spring arm normally overlying said by-pass leading to said impeller chamber, an aperture in said valve plate in registry with said by-pass connected to said discharge manifold, a valve chamber within said valve housing, and means for Withdrawing air from said valve chamher.

4. The structure described in claim 3 in which the valve plate comprises a peripheral frame having the spring finger projecting inwardly therefrom.

5. The structure described in claim 3 in which the valve plate comprises a generally rectangular frame through which the aperture extends, said spring finger extending inwardly from said frame.

6. A centrifugal pump including a housing having a pair of impeller chambers, impellers in said chambers, a common discharge manifold, a boss on said housing, a by-pass extending through said boss communicating with said discharge manifold, a pair of by-passes through said boss connected to said impeller chambers, a valve housin connected to said boss, a valve plate interposed between said valve housing and said boss, said valve plate includin resilient finger means overlying said by-passes leading to said impeller chambers, and means for withdrawing air from said valve housing.

7. A centrifugal pump including a pump housing having a pair of impeller chambers therein, impellers in said chambers, a discharge manifold connected to said impeller chambers, a by-pass through said pump housing communicating with said discharge manifold, a pair of spaced bypasses through said pump housing, a Valve housin enclosing the outer ends of said by-passes, said pair of by-passes being connected to said pair of impeller chambers and said valve housing, a valve plate interposed between said valve housing and said pump housing, said valve plate normally closing said by-passes of said pair, and means for withdrawing air from said valve hous- 8. The structure described in claim 7 in which the spring plate includes a peripheral frame and a pair of spring fingers extending inwardly from said frame, one of said spring fingers being arranged to connect with each by-pass of said pair.

FRED A. WATEROUS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,480,608 Gardner Jan. 15, 1924 1,573,931 Goyne Feb. 23, 1926 1,665,460 Hollander et al. Apr. 10, 1928 1,682,331 Goyne et al. Aug. 28, 1928 1,986,831 Le Valley Jan. 8, 1935 1,997,418 Homschuch et al. Apr. 9, 1935 2,064,754 Ivens Dec. 15, 1936 

